If all matter were made of electrically neutral particles such as neutrons

Options

A. there would be no force of friction
B. there would be no tension in the string
C. it would not be possible to sit on a chair
D. the earth could not move around the sun

Answer

To solve the question, we need to analyze the implications of all matter being made up of electrically neutral particles, such as neutrons. Let's break down the options provided in the question step by step.

### Step 1: Understanding the nature of electrically neutral particles
- **Explanation**: Neutrons are electrically neutral particles, meaning they do not carry any electric charge. This has significant implications for the forces that arise from charged particles, particularly electromagnetic forces.

### Step 2: Analyzing the first option: "There would be no force of friction."
- **Explanation**: Friction is a force that arises from the electromagnetic interactions between charged particles at the surfaces in contact. If all matter were made of neutrons, which are neutral, there would be no electromagnetic interactions to create friction.
- **Conclusion**: This statement is **correct**.

### Step 3: Analyzing the second option: "There would be no tension in the string."
- **Explanation**: Tension in a string is also a result of electromagnetic forces acting between the particles in the string and the objects they are connected to. If all particles were neutral, there would be no electromagnetic forces to create tension.
- **Conclusion**: This statement is **correct**.

### Step 4: Analyzing the third option: "It would not be possible to sit on the chair."
- **Explanation**: Sitting on a chair relies on the frictional force between the chair and the person. If all matter were made of neutral particles, there would be no friction to support the weight of the person sitting on the chair.
- **Conclusion**: This statement is **correct**.

### Step 5: Analyzing the fourth option: "The earth could not move around the Sun."
- **Explanation**: The movement of the Earth around the Sun is governed by gravitational forces, which depend on the masses of the Earth and the Sun. Since neutrons have mass, the gravitational force would still exist regardless of the particles being electrically neutral.
- **Conclusion**: This statement is **incorrect**.

### Final Conclusion
Based on the analysis:
- Correct options: 1, 2, and 3.
- Incorrect option: 4.